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Glyphosate-based herbicides (GBHs) are the most frequently used herbicides worldwide. The use of GBHs is intended to tackle weeds, but GBHs have been shown to affect the life-history traits and antioxidant defense system of invertebrates found in agroecosystems. Thus far, the effects of GBHs on detoxification pathways among invertebrates have not been sufficiently investigated. We performed two different experiments—1) the direct pure glyphosate and GBH treatment, and 2) the indirect GBH experiment via food—to examine the possible effects of environmentally relevant GBH levels on the survival of the Colorado potato beetle (Leptinotarsa decemlineata) and the expression profiles of their detoxification genes. As candidate genes, we selected four cytochrome P450 (CYP), three glutathione-S-transferase (GST), and two acetylcholinesterase (AChE) genes that are known to be related to metabolic or target-site resistances in insects. We showed that environmentally relevant levels of pure glyphosate and GBH increased the probability for higher mortality in the Colorado potato beetle larvae in the direct experiment, but not in the indirect experiment. The GBHs or glyphosate did not affect the expression profiles of the studied CYP, GST, or AChE genes; however, we found a large family-level variation in expression profiles in both the direct and indirect treatment experiments. These results suggest that the genes selected for this study may not be the ones expressed in response to glyphosate or GBHs. It is also possible that the relatively short exposure time did not affect gene expression profiles, or the response may have already occurred at a shorter exposure time. Our results show that glyphosate products may affect the survival of the herbivorous insect already at lower levels, depending on their sensitivity to pesticides. peerReviewed

Understanding the risk of local extinction of a species is vital in conservation biology, especially now when anthropogenic disturbances and global warming are severely changing natural habitats. Local extinction risk depends on species traits, such as its geographical range size, fresh body mass, dispersal ability, length of flying period, life history variation, and how specialized it is regarding its breeding habitat. We used a phylogenetic approach because closely related species are not independent observations in the statistical tests. Our field data contained the local extinction risk of 31 odonate (dragonflies and damselflies) species from Central Finland. Species relatedness (i.e., phylogenetic signal) did not affect local extinction risk, length of flying period, nor the geographical range size of a species. However, we found that closely related species were similar in hind wing length, length of larval period, and habitat of larvae. Both phylogenetically corrected (PGLS) and uncorrected (GLM) analysis indicated that the geographical range size of species was negatively related to local extinction risk. Contrary to expectations, habitat specialist species did not have higher local extinction rates than habitat generalist species nor was it affected by the relatedness of species. As predicted, species’ long larval period increased, and long wings decreased the local extinction risk when evolutionary relatedness was controlled. Our results suggest that a relatively narrow geographical range size is an accurate estimate for a local extinction risk of an odonate species, but the species with long life history and large habitat niche width of adults increased local extinction risk. Because the results were so similar between PGLS and GLM methods, it seems that using a phylogenetic approach does not improve predicting local extinctions.

Using social information can be an efficient strategy for learning in a new environment while reducing the risks associated with trial-and-error learning. Whereas social information from conspecifics has long been assumed to be preferentially attended by animals, heterospecifics can also provide relevant information. Because different species may vary in their informative value, using heterospecific social information indiscriminately can be ineffective and even detrimental. Here, we evaluated how selective use of social information might arise at a proximate level in bumblebees (Bombus terrestris) as a result of experience with demonstrators differing in their visual appearance and in their informative value as reward predictors. Bumblebees were first trained to discriminate rewarding from unrewarding flowers based on which type of &ldquo, heterospecific&rdquo, (one of two differently painted model bees) was next to each flower. Subsequently, these bumblebees were exposed to a novel foraging context with two live painted bees. In this novel context, observer bumblebees showed significantly more social information-seeking behavior towards the type of bees that had predicted reward during training. Bumblebees were not attracted by paint-marked small wooden balls (moved via magnets) or paint-marked non-pollinating heterospecifics (woodlice, Porcellio laevis) in the novel context, indicating that bees did not simply respond to conditioned color cues nor to irrelevant social cues, but rather had a &ldquo, search image&rdquo, of what previously constituted a valuable, versus invaluable, information provider. The behavior of our bumblebees suggests that their use of social information is governed by learning, is selective, and extends beyond conspecifics.

Aim: Biological diversity typically varies between climatically different regions, and regions closer to the equator often support higher numbers of taxa than those closer to the poles. However, these trends have been assessed for a few organism groups, and the existing studies have rarely been based on extensive identical surveys in different climatic regions. Location: We conducted standardized surveys of wadeable streams in a boreal (western Finland) and a subtropical (south-eastern Brazil) region, sampling insects identically from 100 streams in each region and measuring the same environmental variables in both regions. Taxon: Aquatic insects. Methods: Comparisons were made at the scales of local stream sites, drainage basins and entire regions. We standardized the spatial extent of the study areas by resampling regional richness based on subsets of sites with similar extents. We examined differences in genus richness and assemblage abundance patterns between the regions using graphical and statistical modelling approaches. Results: We found that while genus accumulation and rank-abundance curves were relatively similar at the regional scale between Finland and Brazil, regional genus richness was higher in the latter but regional abundance much higher in the former region. These regional patterns for richness and abundance were reproduced by basin and local genus richness that were higher in Brazil than in Finland, and assemblage abundance that was much higher in Finland than in Brazil. The magnitude of the difference in genus richness between Brazil and Finland tended to increase from local through basin to regional scales. Main conclusions: Our findings suggest that factors related to evolutionary diversification might explain differences in genus richness between these two climatically different regions, whereas higher nutrient concentrations of stream waters might explain the higher abundance of insects in Finland than in Brazil.

Antipredator strategies of the pupal stage in insects have received little attention in comparison to larval or adult stages. This is despite the fact that predation risk can be high during the pupal stage, making it a critical stage for subsequent fitness. The immobile pupae are not, however, defenceless; a wide range of antipredator strategies have evolved against invertebrate and vertebrate predators. The most common strategy seems to be ‘avoiding encounters with predators' by actively hiding in vegetation and soil or via cryptic coloration and masquerade. Pupae have also evolved behavioural and secondary defences such as defensive toxins, physical defences or deimatic movements and sounds. Interestingly, warning coloration used to advertise unprofitability has evolved very rarely, even though the pupal stage often contains defensive toxins in chemically defended species. In some species, pupae gain protection from conspecifics or mimic chemical and auditory signals and thereby manipulate other species to protect them. Our literature survey highlights the importance of studying selection pressures across an individual's life stages to predict how ontogenetic variation in selective environments shapes individual fitness and population dynamics in insects. Finally, we also suggest interesting avenues for future research to pursue. This article is part of the theme issue ‘The evolution of complete metamorphosis’.

The work has been supported by the Academyof Finland to A.H. (project 267244) and Natural Environment Research Council (NERC) funding (NE/J020818/1 to M.G.R.; NE/L501852/1 to R.A.W.W.). The incidence of reproductive diapause is a critical aspect of life history in overwintering insects from temperate regions. Much has been learned about the timing, physiology and genetics of diapause in a range of insects, but how the multiple changes involved in this and other photoperiodically regulated traits are inter-related is not well understood. We performed quasinatural selection on reproduction under short photoperiods in a northern fly species, Drosophila montana, to trace the effects of photoperiodic selection on traits regulated by the photoperiodic timer and/or by a circadian clock system. Selection changed several traits associated with reproductive diapause, including the critical day length for diapause (CDL), the frequency of diapausing females under photoperiods that deviate from daily 24 h cycles and cold tolerance, towards the phenotypes typical of lower latitudes. However, selection had no effect on the period of free-running locomotor activity rhythm regulated by the circadian clock in fly brain. At a genomic level, selection induced extensive divergence from the control line in 16 gene clusters involved in signal transduction, membrane properties, immunologlobulins and development. These changes resembled those detected between latitudinally divergent D. montana populations in the wild and involved SNP divergence associated with several genes linked with diapause induction. Overall, our study shows that photoperiodic selection for reproduction under short photoperiods affects diapause-associated traits without disrupting the central clock network generating circadian rhythms in fly locomotor activity. Publisher PDF

Allocation to different components of defence has been suggested as an explanation for the existence of multiple aposematic morphs in a single population. We tested whether there are trade-offs between warning colouration and chemical defence or whether these have an additive effect when combined, using blue tits (Cyanistes caeruleus) as predators and the polymorphic wood tiger moth (Arctia plantaginis) as prey. We used artificial edible models (with and without the moths’ defensive fluids) with paper wings whose colour and pattern properties matched those of real moths. When the models were presented sans defensive fluids or when the fluids were presented without colour cues, we detected no differences in initial avoidance between the two morphs. However, when the colour and chemical cues were combined, differences emerged. White wings elicited higher latency to approach regardless of the defensive fluids applied on them. After approach, however, the defensive fluids of both morphs presented on moth models elicited higher latency to attack than a water control, hinting at a repellent odour. Fluids of white moths rendered lower amounts of prey eaten regardless of wing colour, while yellow moths’ fluids provoked the highest occurrence of beak wiping behaviour. Our findings highlight the importance of accounting for interactive effects between different signal modalities, as these can create patterns not detectable when examined in isolation. Understanding these interactions is vital to determine how different components of multimodal warning displays provide protection at different stages of a predation event and, potentially, how multiple morphs can co-occur in a population. There are many things that can stop a predator attacking a prey such as looking scary or smelling bad, but if a predator does take a bite, tasting bad can make the difference between life and death for the prey. When combined with bright conspicuous colours, both repellent odours and deterrent tastes (i.e. chemical defences) can help predators learn to avoid unprofitable prey. However, it is unclear whether it is really the sum of these visual and chemical signals that most effectively deters predators or whether one is more important than the other. Examining the effects of warning colour and chemical defence in white and yellow wood tiger moths on wild-caught birds, we show that neither aspect of the moths’ defence in isolation is as effective for predator deterrence as the sum of both.

Made available in DSpace on 2015-10-21T13:13:04Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-03-01. Added 1 bitstream(s) on 2015-10-22T09:52:00Z : No. of bitstreams: 1 WOS000351458500010.pdf: 1109708 bytes, checksum: 67b46d77c556852b6b2a5bf0a606d9e1 (MD5) Academy of Finland Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) FRGS of Ministry of Higher Education, Malaysia Spanish Ministry of Science and Technology EU CONICET Companhia Energetica de Minas Gerais (Peixe Vivo Program) PD ANEEL/CEMIG Fundacao de Amparo a Pesquisa de Minas Gerais INPA Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Claude Leon Postdoctoral Fellowship Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Programa de Apoio a Fixacao de Doutores no Amazonas - FIXAM/AM fellowship Australian Research Council Swiss National Science Foundation Swiss Federal Office for the Environment from Switzerland The hypotheses that beta diversity should increase with decreasing latitude and increase with spatial extent of a region have rarely been tested based on a comparative analysis of multiple datasets, and no such study has focused on stream insects. We first assessed how well variability in beta diversity of stream insect metacommunities is predicted by insect group, latitude, spatial extent, altitudinal range, and dataset properties across multiple drainage basins throughout the world. Second, we assessed the relative roles of environmental and spatial factors in driving variation in assemblage composition within each drainage basin. Our analyses were based on a dataset of 95 stream insect metacommunities from 31 drainage basins distributed around the world. We used dissimilarity-based indices to quantify beta diversity for each metacommunity and, subsequently, regressed beta diversity on insect group, latitude, spatial extent, altitudinal range, and dataset properties (e.g., number of sites and percentage of presences). Within each metacommunity, we used a combination of spatial eigenfunction analyses and partial redundancy analysis to partition variation in assemblage structure into environmental, shared, spatial, and unexplained fractions. We found that dataset properties were more important predictors of beta diversity than ecological and geographical factors across multiple drainage basins. In the within-basin analyses, environmental and spatial variables were generally poor predictors of variation in assemblage composition. Our results revealed deviation from general biodiversity patterns because beta diversity did not show the expected decreasing trend with latitude. Our results also call for reconsideration of just how predictable stream assemblages are along ecological gradients, with implications for environmental assessment and conservation decisions. Our findings may also be applicable to other dynamic systems where predictability is low. Finnish Environment Institute, Natural Environment Centre, Biodiversity, Oulu, Finland Departamento de Ecologia, Universidade Federal de Goiás, Goiânia, GO, Brazil Department of Aquatic Ecology, Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Zürich, Switzerland School of Biological Sciences, Universiti Sains Malaysia, Penang, Malaysia Biology Department, Faculty of Science, University of Tabuk, Tabuk, Saudi Arabia Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden Departament d'Ecologia, Grup de Recerca Freshwater Ecology and Management (FEM), Universitat de Barcelona, Barcelona, Catalonia, Spain LIESA-CONICET-Universidad Nacional de la Patagonia SJB, Chubut, Argentina Departamento de Biologia Geral, Instituto de Biologia Geral, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil Department of Integrative Biology, University of Guelph, Guelph, ON, Canada Laboratory of Entomology, School of Biological Sciences, Pontifical Catholic University of Ecuador, Quito, Ecuador IRD, Institut de Recherche pour le Développement, Laboratoire Evolution, Génomes et Spéciation, Gif-sur-Yvette, France School of Biological Sciences, The University of Hong Kong, Hong Kong SAR, China Laboratorio de Ecología Acuática Colegio de Ciencias Biológicas y Ambientales Universidad San Francisco de Quito, Quito, Ecuador Department of Bioscience, Aarhus University, Silkeborg, Denmark Instituto Nacional de Pesquisas da Amazônia, Coordenação de Biodiversidade, Manaus, AM, Brazil 18Department of Biology, University of Copenhagen, Copenhagen, Denmark Departamento de Botânica e Ecologia, Universidade Federal do Mato Grosso, Cuiabá, Brazil Departamento de Ciências Biológicas e da Saúde, Universidade Federal de Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, Brazil Section of Conservation Biology, Department of Environmental Sciences, University of Basel, Basel, Switzerland Balaton Limnological Institute, Centre for Ecological Research, Hungarian Academy of Sciences, Tihany, Hungary Department of Conservation Ecology and Entomology, Stellenbosch University, Stellenbosch, South Africa Instituto de Biociências, UNESP - Universidade Estadual Paulista, Rio Claro, São Paulo, Brazil Institute for Applied Ecology, University of Canberra, Canberra, ACT, Australia Department of Zoology, University of Otago, Dunedin, New Zealand. Universidade Estadual Paulista, Instituto de Biociências, Departamento de Ecologia, UNESP - Rio Claro, São Paulo, Brazil Spanish Ministry of Science and Technology: HID98-0323-C05 Spanish Ministry of Science and Technology: REN2001-3438-C07 EU: 226874 CONICET: PIP 5733 PD ANEEL/CEMIG: GT-487 Fundacao de Amparo a Pesquisa de Minas Gerais: FAPEMIG PPM-00077/13 FAPESP: 2013/50424-1 CNPq: 403949/2013-0 Australian Research Council: FT110100957

A checklist of the ‘lower Brachycera’ of Finland is presented. This part of the complete checklist of Finnish Diptera covers the families Acroceridae, Asilidae, Athericidae, Bombyliidae, Mythicomyiidae, Rhagionidae, Scenopinidae, Stratiomyidae, Tabanidae, Therevidae, Xylomyidae and Xylophagidae.

The presence/absence data of twenty-seven forest insect taxa (e.g. Retinia resinella, Formica spp., Pissodes spp., several scolytids) and recorded environmental variation were used to investigate the applicability of modelling insect occurrence based on satellite imagery. The sampling was based on 1800 sample plots (25 m by 25 m) placed along the sides of 30 equilateral triangles (side 1 km) in a fragmented forest area (approximately 100 km2) in Evo, S Finland. The triangles were overlaid on land use maps interpreted from satellite images (Landsat TM 30 m multispectral scanner imagery 1991) and digitized geological maps. Insect occurrence was explained using either environmental variables measured in the field or those interpreted from the land use and geological maps. The fit of logistic regression models varied between species, possibly because some species may be associated with the characteristics of single trees while other species with stand characteristics. The occurrence of certain insect species at least, especially those associated with Scots pine, could be relatively accurately assessed indirectly on the basis of satellite imagery and geological maps. Models based on both remotely sensed and geological data better predicted the distribution of forest insects except in the case of Xylechinus pilosus, Dryocoetes sp. and Trypodendron lineatum, where the differences were relatively small in favour of the models based on field measurements. The number of species was related to habitat compartment size and distance from the habitat edge calculated from the land use maps, but logistic regressions suggested that other environmental variables in general masked the effect of these variables in species occurrence at the present scale.

Assimilation of cow liver by Lucilia illustris (Meigen) larvae was studied in the laboratory. The larvae were cultured from hatching to the end of development in the respiration chambers of an infra-red gas analyser (IRGA), and respiration was measured as CO2 production. Assimilation was calculated in both carbon and energy units. In this organism the Cr203 indicator method proved unsuitable for measuring food consumption. In early larval development respiration showed two linear phases, which are suggested to be correlated with the first two instars. Both the cumulative and the instantaneous net production efficiency, K2 (production/assimilation), were calculated. Integration of the latter to the final larval weight produced results similar to those obtained by direct determination. K2 varied both with temperature and with the developmental stage of the larvae (weight). Efficiency was highest during the most intense growth phase, or a little before it, then being 88 % in carbon units (90 % in energy units) at 25 to 300C. At this optimal temperature the cumulative K2 to the end of the feeding period was 82 % (84 %); in changing temperature conditions the corresponding K2 was 77 0 (79 %). The value of instantaneous concepts in bioenergetic research and the application of IRGA to measurements of animal respiration is discussed.